White blood cells are the main component of the body's defense against disease. For example, the rate of leukocytes in the blood at 6 years old is 5–12. They protect the body from invading microorganisms and cells with mutated DNA and cleanse the body. Platelets are needed to "repair" blood vessels when they are damaged; they also provide growth factors and healing. It is worth learning more about the rate of leukocytes in a child of 6 years old (also older and younger).
To check the number of leukocytes, you need to take a complete blood count. The norm of white blood cells in the blood of adult men and women is 4-9x109. In some laboratories, the reference values (norms) of the content of leukocytes are expanded and amount to 3, 2-10, 6x109. In children, these figures are higher: at the age of one year, there are 6.5-12.5 x 109 of these cells in the blood, up to three years - 5-12 x 10 9, up to six - 4, 5-10 x 109, up to sixteen - 4, 3-9, 5 x 109.
Characteristics of white bodies
Although leukocytes and erythrocytes originate from hematopoietic stem cells in the bone marrow, they are verydiffer from each other in many significant ways.
For example, the first is much less than the second: usually their number is from 5000 to 10000 per 1 µl. They are also larger than them and are the only formed elements that are considered complete cells that have a nucleus and organelles. While there is only one type of red blood cell, there are many types of white blood cells. Most have a much shorter lifespan than red blood cells, some have a short lifespan of only a few hours or even a few minutes in the case of an acute infection.
One of the most striking characteristics of leukocytes in the urine of a 6-year-old child is their movement. While red blood cells spend their days circulating in the blood vessels, white blood cells usually leave the bloodstream to carry out their protective functions in the tissues of the body. For leukocytes, the vasculature is simply a highway in which they travel and soon emerge to reach their true destination. When they arrive, they are often given different "names" such as macrophage or microglia, depending on their function.
Once they leave the capillaries, some of them will take fixed positions in the lymphatic tissue, bone marrow, spleen, thymus or other organs. Others will move through tissue spaces much like amoebas, continuously expanding their plasma membranes, sometimes wandering freely, and sometimes moving in the direction in which they manifest chemical signals.
This white body attraction is due topositive chemotaxis (literally, "movement in response to chemicals") - a phenomenon in which injured or infected cells and nearby white blood cells emit the equivalent of a chemical "911" call, sending more "rescuers" to the right place.
In clinical medicine, differential counts of types and percentages of white blood cells present are often key indicators in diagnosis and treatment. Therefore, if there are 6-10 leukocytes in the urine, then they can be called the norm and nothing to worry about. But is this value normal for adults? Yes. For example, if women have 6, 6 leukocytes in urine, then this is an indicator of he alth.
Classification of white bodies
When scientists first began to study the composition of blood, it quickly became apparent that leukocytes could be divided into two groups, depending on whether they contained peculiar granules in the cytoplasm:
- Granular species are distinguished by abundant granularity in the cytoplasm. They include neutrophils, eosinophils, and basophils. In children at 6 months, leukocytes will be normal at a value of 6, 6.
- Although granules are not completely absent from agranular leukocytes, they are much smaller and less obvious. This species includes monocytes that mature into macrophages. The latter are phagocytic and lymphocytes that arise from a line of lymphoid stem cells. The norm of leukocytes at 6 years old is 5–12.
Normal amount in women
The number of white bodies is oneof the most significant characteristics in a blood test. In the body of a woman, leukocytes should be from 3.2109/l to 10.2109/l. A change in the degree of immune cells occurs in 2 cases: with diseases of the blood and hematopoietic materials and with pathologies of other organs and systems. The phase of the monthly cycle with a hormonal background also has a great influence on the number of bodies. In addition, leukocytes in the blood during pregnancy "jump" very much, and it is considered normal if their level reaches 15109/l.
Norms for men
Their blood should have from 4 up to 9109/l leukocytes. Their degree in the male body varies little compared to other groups of patients. Conditions like these can affect your white blood cell count:
- unaccustomed physiological stress;
- stress;
- changing the food menu.
Leukocytes 6, 6 in this case is normal.
In children
As a rule, if in the organisms of older people the number of white bodies is approximately equal, then in children it varies significantly. Their degree fluctuates even depending on the age of the child:
- in infants up to a month: 8 - 13109/l;
- children from 2 to 12 months: 6 - 12109/l;
- for a child from one to 3 years old: 5 - 12109/l;
- for children from 3 to 6: 5 - 10109/l;
- for children from 6 to 16: 5 - 9, 5109/l.
The increased content of immune cells is explained by the fact that a greater number ofvarious actions. All organs and systems of the child are rebuilt and adapted to existence outside the mother's womb. In addition, the development of immunity takes place, which generates an increase in leukocytes in the blood. As they grow older, their degree decreases. If this is done, then the immune system has strengthened.
Granular leukocytes
What does the presence of granular white bodies indicate on a blood test printout? We will consider their meaning in order from the most common to the least known. All of them are produced in the red bone marrow and have a short lifespan, from a few hours to a few days. They usually have a lobed core and are classified according to what type of spots best highlights their granules.
1) The most abundant of all white blood cells are neutrophils, typically accounting for 50-70 percent of the total. They have a diameter of 10-12 microns, much larger than erythrocytes. They are called neutrophils because their granules show up most clearly with chemically neutral stains (neither acids nor bases).
Neutrophils respond quickly to the site of infection and are efficient phagocytes with a preference for bacteria. Their granules include lysozyme, an enzyme capable of lysing or destroying: bacterial cell walls; oxidizing agents such as hydrogen peroxide; defensins; proteins that bind; purge bacterial and fungal plasma membranes so cell contents flow.
Abnormally highneutrophil counts in the assay indicate infection and/or inflammation, especially those caused by bacteria, but are also found in burn patients and others under unusual stress. A burn injury increases neutrophil proliferation to fight off infection that may result from the destruction of the skin barrier. Low rates may be due to drug toxicity and other disorders, showing an individual's increased susceptibility to infection.
2) Eosinophils usually make up 2-4 percent of the total white blood cell count. They also have a diameter of 10-12 microns. Their granules stain best with an acid stain known as eosin. The eosinophil nucleus typically has two to three lobes and, if properly stained, the granularity will take on a bright red and orange color.
Eosinophil granules include antihistamine molecules that counter the action of histamines and inflammatory chemicals produced by basophils and mast cells. Some eosinophil granules contain molecules that are toxic to parasitic worms that can enter the body through the skin or when a person consumes raw or undercooked fish and meat.
Eosinophils are also capable of phagocytosis and are especially effective when antibodies bind to the target and form an antigen-antibody complex. High eosinophil counts are typical in patients with allergies, parasitic worm infestations, and some autoimmune diseases. Low rates may be due to toxicity and stress.
3) Basophilsare the least common cells, usually constituting no more than one percent of the total white blood cell count. They are slightly smaller than neutrophils and eosinophils: 8-10 microns in diameter. Basophil granules stain best with basic (alkaline) stains. Basophils contain a curved nucleus, which is almost invisible under the cytoplasm.
In general, they block the spread of toxins in the tissues and "force" other types of cells to actively move towards the lesion of the body. They are similar in this factor to mast cells. Previously, the latter were considered basophils, but they left the bone marrow already in a mature form, which allowed scientists to separate these 2 types.
Basophil granules secrete histamine, which promotes inflammation, and heparin, which resists blood clotting. High levels of basophils in the analysis are associated with allergies, parasitic infections and hypothyroidism. Low levels indicate pregnancy, stress, and hyperthyroidism.
Agranular leukocytes
What does the presence of this type of cells in a blood test indicate? Agranular bodies contain less visible granules in their cytoplasm than granular leukocytes, 6, 6 for which is normal. The nucleus is simple in form, sometimes indented, but without separate lobes. There are two main types of agranulocytes: lymphocytes and monocytes.
1) The former are the only formed element of the blood, which arises from lymphoid stem cells. Although they are originally formed in the bone marrow, most of themsubsequent development and reproduction occurs in the lymphatic tissues. Lymphocytes are the second most common type of white blood cell, accounting for about 20-30 percent of all blood cells, and are essential for the immune response.
There are three main groups of lymphocytes that include natural killer cells: B and T. Natural killer (NK) cells are able to recognize cells that do not express "self" proteins on their plasma membrane or contain foreign or abnormal markers. These non-self-celled cells include virus-infected cancer cells and others with atypical surface proteins. Thus, they provide generalized, non-specific immunity. Large lymphocytes are usually NK cells.
B and T-bodies play an important role in protecting the body from specific pathogens (pathogens) and are involved in specific immunity. One form of B cell (plasma) produces antibodies or immunoglobulins that bind to specific foreign or abnormal components of plasma membranes. This is also called the immune system (humoral).
T cells provide cellular level protection by physically attacking foreign or diseased pathogens. The memory cell is a set of B- and T-cells that are formed after the impact of the "aggressor" and quickly respond to subsequent attacks. Unlike other white blood cells, memory cells live for many years.
Abnormally highindicators of lymphocytes are characteristic of viral infections, as well as some types of cancer. Abnormally low values indicate long-term (chronic) illness or immunosuppression, including those caused by HIV infection and drug therapy that includes steroids.
2) Monocytes are derived from myeloid stem cells. They usually make up 2-8 percent of the total white blood cell count. These cells are recognized by their large size (12-20 µm) and indented or horseshoe-shaped nuclei.
Macrophages are monocytes that have left the circulation and phagocytize debris, foreign pathogens, worn-out red blood cells and many other dead, exhausted or damaged cells. Macrophages also release antimicrobial defensins and chemotactic chemicals that attract other white blood cells to the site of infection. Some macrophages occupy fixed locations while others wander through the tissue fluid.
Abnormally high number of monocytes in the analysis is associated with viral or fungal infections, tuberculosis, some forms of leukemia and other chronic diseases. Abnormally low readings are usually caused by bone marrow suppression.
Leukopenia
A condition in which too few white blood cells are produced. If this condition is expressed, the individual cannot prevent the disease. Excessive proliferation of white blood cells is known as leukocytosis. Although their numbers are high, the cells themselves are often dysfunctional, leading to an increased risk of disease. But if the child has white blood cells 6, 6, then you should not worry. After all, thisvalue is within the norm. The following is a white blood cell count for leukopenia.
Leukemia
Cancer with an abundance of white blood cells. It may include only one specific type of white blood cell from the myeloid (myelocytic leukemia) or lymphoid lineage (lymphocytic leukemia). In chronic leukemia, mature white bodies accumulate and do not die. In acute leukemia, there is an overproduction of young, immature cells. In both cases, the cells do not function correctly. The figures are shown in the photo below.
Lymphoma
A form of cancer in which masses of malignant T and/or B lymphocytes accumulate in the lymph nodes, spleen, liver and other tissues. As with leukemia, the malignant white blood cells do not function properly and the patient is vulnerable to infection. Some forms of lymphoma tend to progress slowly and respond well to treatment. Others tend to develop rapidly and require aggressive treatment, without which they are fatal. For example, in children, the rate of leukocytes at 6 months is 5.5–12.5, which means that these indicators are not a pathology. Whether they are higher or lower, you can sound the alarm.
Platelets
Sometimes platelets can be seen in the transcript of the analysis (as in the table above), but since this name suggests that they are a type of cell, this is inaccurate. Platelets are not platelets, but rather a piece of cytoplasm called a megakaryocyte that is surrounded by a plasma membrane. Megakaryocytes occurfrom myeloid stem cells, and are large, typically 50-100 µm in diameter, and contain an enlarged, lobed nucleus.
Typically, thrombopoietin, a glycoprotein secreted by the kidneys and liver, stimulates the proliferation of megakaryoblasts, which mature into megakaryocytes. They remain in bone marrow tissue and eventually form extensions of progenitor platelets that extend through the walls of bone marrow capillaries to release into the circulation thousands of cytoplasmic fragments, each bounded by a small plasma membrane.
These closed fragments are platelets. Each megakarocyte releases 2000-3000 of them during its lifetime. After the release of platelets, the remnants of megakaryocytes, which are slightly larger than the cell nucleus, are consumed by macrophages.
Diseases and platelets
Thrombocytosis is a condition in which there are too many of them. This can cause unwanted blood clots (thrombosis), a potentially fatal disorder. If there are not enough platelets, called thrombocytopenia, the blood may not clot properly and excessive bleeding can occur.
We looked at the percentage of leukocytes and platelets in a blood test, which can cause them to deviate from the norm.
